Thread-controlling mechanism for sewing-machines.



R. G. WOODWARD.

THREAD CONTROLLING MECHANISM FOR SEWING MACHINES. APPLICATION FILED OCT. 21. 1906.

3 SHEETS-SHEET 1.

Patented Apr. 13, 1915.

R. G. WOODWARD.

THREAD CONTROLLING MECHANISM FOR SEWING MACHINES. APPLICATION FILED OCT. 27. I906.

Patented Apr. 13, 1915.

3 SHEETS-SHEET 2.

R. G. WOODWARD.

THREAD CONTROLLING MECHANISM FOR SEW!NG MACHINES.

APPLICATION FILED OCT. 27. I906.

3 SHEIITB-BHEET 8.

Patented Apr. 13, 1915.

RUSSEL G. WOOJDW MACHINE COMP t Specification of Letters Patent.

OF WAUKJEGAN, ILLINOIS, ASSIGNOR 'IO UNION SPECIAL OF CHICAGO, ILLINOIS, 'A CORPORATION OF ILLINOIS.

a 1:1 Elm-CONTROLLING MECHANISM FOR SEWING-MACHINES.

Patented Apr. I3, IOIfi.

Application filed October 27, 19%. Serial No. 340,896.

To all whom it may concern:

Be it known that I, RUssEnG. WOODWARD, a citizen of the United States, residing at IVaukegan, in the county of Lake, State of Illinois, have invented certain new and useful Improvements in Thread-Controlling Mechanism for Sewing-Machines, of which the following is a description, reference being had to the accompanying drawing and to the letters and figures of reference marked thereon.

My invention relates to take-up mechanisms for sewing machines, and while as to some of its features it may be used for various purposes, said improvements are more particularly adapted to operate in connection with a looper of a chain stitch machine.

An object of my invention is to provide a take-up mechanism for a thread-carrying implement, which keeps the thread under constant control during all the movements of said thread-carrying implement.

A further object of my invention is to provide a take-up mechanism which includes means whereby upon the accidental backward turning of the machine the thread is disengaged from the take-up, and all danger of winding the thread into the take-up is therefore avoided.

These and other objects will in part be obvious, and in part be hereinafter more fully described.

My invention consists in the novel parts and improvements hereinafter shown and described.

In the accompanying drawings, which form a part of this specification 5 Figure 1 is a front elevation of a sewing machine provided with my improvements, the front of the casing and the work plate being removed to more clearly show the operating mechanism; Fig. 2 is a front view of the base portion of the machine shown in Fig. 1 on an enlarged scale, certain of the parts being broken away and omitted to more clearly show the invention; Fig. 3 is a front view of my thread-controlling cam, also showing the thread guide and its relation thereto; Fig. 4 is a view similar to Fig. 3 of the threadcontrolling cam in a different position; Fig. 5 1s a view similar to Fig. 3 of the threadcontrolling cam in another position; and V Fig. 6 shows a modification in the form of my thread-controlling cam.

In the drawings, the bed plate 6 has rising therefrom an overhanging arm 20, which carries at its forward end the usual needle head 21. Reciprocating in said needle head 21 is a needle bar 22, carrying a needle 23. The needle bar receives its reciprocation from a needle lever 2a, which is pivoted at 25 to the overhanging arm, and is connected by a link 26 to said needle bar. Ihis needle lever is oscillated about its pivot by a link 27, which is pivoted to said needle lever at one end, and is operatively connected at its other end to an eccentric 28, on the main shaft 10. Rigidly secured to the needle lever is a thread-controlling arm 29, which cooperates with the tension 30 and thread guide31, in controlling the needle thread.

Ihe needle lever 24: is provided with an extension-31, which is connected by means of a link 7 to the looper carrier 2. 'I he looper 1 is mounted in the usual manner in the looper carrier 2, which in turn is pivotally connected to a looper support 3, mounted on a shaft I, carried by the brackets 5, 5, rising from the bed plate 6.

'Ihe looper receives its lateral or needleavoiding movement through the arm 8, which is fixed to the looper support 3, and at its upper end is pivoted to an eccentric strap 9, which cooperates with an eccentric car ried by the main shaft 10.

It will be noted that as the needle lever is oscillated the looper carrier is also oscillated in timin therewith through the link 7. The link is pivoted to the looper carrier at a point 32. This point 32 is a shorter distance from the pivotal point of the looper v carrier, so that while the point of connection between the link 7 and the carrler moves in timing with the point of connection bep tween the link 7 and the needle lever extension, the looper moves considerably faster.

The thread for the looper is led though a..

tension 33 carried by the head of the mai The thread-controlling cam chine, thence through a thread guide 34 at the lower end of the needle lever extension and from the thread guide 34 said thread passes through my improved take-up mech- 5 anism to the looper 1.- I Inasmuch as the looper moves at a greater l speed than the thread guide 34, it is necessary to provide some means for taking care ,of the slack produced, in the looper thread by this difference in the timing of these parts, and also tocare for the usual slack formed and to draw ofi' sufiicient .thread from the supply for the forming of the stitches. For this purpose I have provided my improved take-up mechanism, which as shown in thepresentembodiment of my invention comprises a thread-controlling cam 19, mounted on the main shaft 1 intermediate" the thread guide 34 and the looper. Cooperating with said threadcontrolling caml9 is a thread-retaining device 17, which operates to properly position the looper thread relative to the thread-controlling cam. Said thread-retaining device 17,- as shownin the drawing, is formed from a single wire 14, carried by a plate 13, which is adjustably secured to the bed plate 6, by means of a slot 11 and a screw 12. Said thread-retaining wire 14 extends upwardly 39 land backwardly asshown at 18 to a position inside of the smallest radius of said threadcontr'olling cam. The thread-retaining wire is then bent downwardly and outwardly, as at 17, to a position outside of the largest r radius of said thread-controlling cam. The

ends of the thread wire 14, which extend up on each side of the thread controlling cam, are preferably joined as at 15, t-J It will be obvious from the above description, that I have provided a threadguiding or retaining device which operates to hold the thread at each side of the threadcontrolling cam. Furthermore inasmuch as the thread retainer extends to a position inside of the smallest radius of the threadconti'olling cain, said thread-controlling-cam will be constantly in engagement with the looper thread'and consequently said looper thread will be under control continually during all the movements of the looper.

'With the thread-retaining device shaped as shownin the drawings, my thread-con- Y trolling inechaiiism may be easily threaded, as all that is necessary is to slip the thread;

M running over the thread guide 34 to. the

looper, underneath the forwardly projeeting portion 17 of the thread-retaining wire. turning in the ,direction indicated by the arrow in Figs. 3,

80 4'and 5, carries thexthread into the thread ,gslot' formed by the thread wire, "and the oontinued movement of the thread cam holds the thread withinsa d; thread-guiding member. L

If for any reason the machine is accidentally turned in the wrong direction, the thread-controlling cam immediately forces the thread down the thread slot and out of said thread-guiding member, and, therefore,

all liability of the thread being woundup by the thread cam on the backward turning of said cam is avoided. -Furthermore, when a single thread cam is used, instead of the double cams as heretofore, with the threadretaining wire on each side of the saidcam, the liability of winding the thread into the thread cam upon the breaking of the thread or the turning of the machine in the wrong direction, is also avoided. .The purpose of adjusting the supporting plate 13 which carries the thread-guiding members, .is to properly locate said thread-guiding members on each side of the thread-controlling cant. l

The operation of my thread-controlling cam is as follows: Starting with the needle at its highest point, which would place the looper ,in its most forward position, the thread-controlling cam is in the position shown in Fig. 3, and the looper thread is carrier substantially straight across from the guide on oneside of the thread-controllin'g member to the guide on the other side of said member. At this time the looper thread also extends from the previous stitch through the needle loop on the looper to the eye of the looper at the point which is at considerable distance to the left of the needle, andthenback through the eye at the heel of the looper. When the looper starts to return, the thread eye 34 on the needle lever. extension moves to the right, as viewed in Fig. 1, but at a rate of travel' slower than the looper, thus causing slack in the looper thread. The looper also'is -withdrawing from the needle loop at this time, and is giving up the thread drawn by the movement of the looper eye beyond the lineof seam or the needle. The threadcontrolling cam moves from the position shown in Fig. 3 to that shown in Fig. 4, and this slack in the thread is taken up, drawing the looper thread back through the eye of the looper, so as to properly position the thread for the entrance of the needle into the looper loop, and at the sametime when the looper'thread is under strain thread is drawn bythe thread-controlling cam, and thread guide 34 from the supply through the tension 33. This operation of taking up slack continues until the needle gets well into the loop of thread formed by the looper, and the thread-controlling cam has passed slightly the position shown in Fig. 4, when the thread slips off th e enlargement A or is .cast off. The needle loop is now castoff from the looper, and is' being drawn up closely to the underside of the material.

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and the looper thread is slack, so as not to interfere with the drawing up of this needle loop.

looper eyes, and the take-up to the threadguide on the needle lever extension. As the looper moves forward to enter the needle loop, the thread guide 34 moves forward and slack is caused in the looper thread. The enlargement C, Fig. 5, is now coming into engagement with the thread between the thread guides and the slack is taken up, said enlargement pulling the slack formed in front of the looper as it moves toward the needle through the looper eyes. After the looper enters the needle loop the enlargement C passes the thread and slack is gradually given up to the movements of the looper; said looper moving beyond the needle and forming the looper thread loop requiring thread at this time. The feed of the fabric commences as the looper is reaching the forward end of the stroke, and the thread cam is approaching the position shown in Fig. 3, so that thread is easily drawn from the supply for the feeding of the material as the thread. is at this time substantially straight from one thread guide to the other. The feed commences, however, while slack is still retained by the thread cam, so that the drawing of the thread from the sup ly is slow at first. followed by a rapid pul ing from the supply as the slack is exhausted. It will be noted, therefore, that my improved thread cam operates, starting with the position shown in Fig. 3, to first take-up slack quickly, then allow slack to be given up quickly, take up slack quickly a second time, and to slowly allow feed of thread from the supply, and finally the rapid feeding ahead of the thread by the movement of the material.

lln. my modified form of take-up shown in Fig. 6, l have provided my thread-controllingcam with asecond enlargement slightly in the rear of the enlarged portion of the thread cam shown in Figs. 3, 4t and 5. In the operation of my machine, this form of thread cam operates practically in the same manner as the thread-controlling cam shown in the other figures, except that after the thread has been cast ofi' by the thread-controlling cam, when the enlargement A passes the thread guides, the thread is again slightly taken up by the enlargement B to straighten out the thread between the loop pulled up to the throat plate and .the front eye of the looper. This threadcontrolling cam operates to keep the looper thread constantly under control in the same manner as the thread-controlling cam shown in the other figures. Said cam will also operate to hold the "thread within the thread guide and to cast the thread from the thread guide upon the accidental backward turning of the machine.

It will be noted that the thread guides are located in advance of the center of the takeup, and have an open mouth extending toward the front of the machine, whereby the same is easy of access for the purpose of threading.

While ll haveshown my thread guides as formed from a wire secured to the base plate and extending up into proper relation to the thread-controlling cam, it will be obvious that said thread guides may be formed from sheet metal or in any other way, as long as the relative position of said guides to the thread-controlling cam is maintained.

llt will be obvious that many minor changes in the details of the construction herein shown may be made without departing from the spirit of my invention. It will also be obvious that said take-up mechanism may be applied to the needle thread, or used in any other relation in a machine of the character herein disclosed, for the purpose of controlling the thread leading to a thread-carrying implement.

Having thus described my invention, what ll claim as new and desire to secure by Letters Patent, is:

1. A looper, means for operating the same, and a rotary take-up for the looper thread, including a thread-controlling element, means for operating said element, and means to retain the thread against the face of he thread-controlling element, said lltl thread on the forward movement of the looper, and control the slack as it is given to the looper, and to take up thread and again give slack thread to the looper on its backward movement, and control the slack given to the looper in its backward move- 'ment.

3. A rotary take-up including in combination, a thread-controlling member, means for rotating said member, and means to retain the thread against the operative face of a said thread-controlling member, saidh'etain- 5 thread-controlling member; substantially as described.

4. A rotary take-up including in combination, a thread-controlling member'and means to retain the thread against the erative face of said thread-controlling me her, said retaining means having an open mouth extending beyond the maximum diameteryof' the thread-controlling member for convenience in threading.

5: A rotary take-up including in combina tion,-a thread controllingmember, and means to retain the thread against the operative face .of said thread-controllin'g member, said retaining means hav' g an .open" mouthextending beyondrthe-ma imum diameter of the thread-controlling member for convenience in threading and a support for sa d retainingmeans located' in advanceof the vcenter of the thread-contrglli'n'g member;

substantially as described. J

6. A rotary take-up including irrcombina tion, a thread-controlling member neans t'o operate said thread-controlling member, and

means to retain the thread in operative position relative to said thread controlling member, and also to deflect the thread out of thepath of the tliread'econtrolling. member when the same is accidentallyturned in the wrong direction whereby the thread is ,pre-

controlling member; substantially as described.

7. A rotary take-up including in combination, a thread-controllingmember, means for rotating the same, a thread-retaining device holding the thread at all timesin operative position against thethread-controlling member, s'aid thread retaining device having a thread guiding slot extending fro i na point inside of the minimum diameter 0f the thread controlling member to a point outside vented from being wound up in thathreadthread across the operative face of said thread-controlling?device, said thread-guiding means having open ended slots between which the thread controlling device projects, said slots extending froma point inside of the minimum diameter of the thread controlling device, to a point outside the maximum diameter, therotation ofsaid threadcontrollin device maintaining the thread at 'the top o said thread-guiding slots; substantially as described 10. In a sewing machine, the combination with a looper, means for operating said looper, a thread guide through which the looper thread is led to the looper, said thread guide being movable forward and backward in timed relation to the 'looper and at a speed differing therefrom, a rotary take up 2 cam engaging the looper thread between said thread guide and looper for controlling tlte slack of the looper thread, and thread guides located at opposite sides of said cam for engaging the looper thread and holding "said thread in contact with said cam.

' 11. In a sewing machine, the combination with a looper andmeans for operating the same, of a thread-controlling device and means for'operatin'g said device, whereby the said, device operates to take up the slack thread caused by the receding movement of the looper and to pull thread from the supply substantially as described.

12. In a sewing machine, the combination 1 with a looper and means for operating the same, of a rotary take-up acting upon the looper thread and operating to'take up,;pull off and allow the 'looper to feed the thread while the same is moving forward; substantially as' deScribed. p 13. A thread-controlling mechanism including in combination, thread guides, means 1 for supporting said thread guides in adjusted positions, a thread-controlling cam ar-' ranged to operatebetween said thread guides, and means for rotating said cam the adjustment of said guides being at substanthe maximum diameter thereof, whereby the/ tially right angles to theplane of the thread rotation of the thread-controllingelement- 'tendsto continuously hold thethread at the inner end or said\thread-guiding slot; s bstantially asdescribedl Y 8. A rotary take-up including in combination, a thread-controlling member, means for rotating said member, a vertically arranged thread-retaining wire extending on each side of said takeupinemben and bent.back- -*ward to form thread guides,the ends of said thread wires being joined in ,frpnt of the a thread-controlling member; substantially as described. l f 9 A rotary take up including combination, a thread 'cofltrolling device, means for rotating said device, meansto guide the controlling cam; substantially as described.

14. A thread-controlling mechanism in upon itself to orm threa guides, a threada controllingcam arrangedwithin the said U- shaped member and engaging a thread pass-- mg through saidthread guides, and means for operating said cam; substantially as described.

16. A thread-controlling mechanism including in combination, an adjustable plate, means for holding the same in its adjusted position, a thread-guiding Wire fixed to said plate and extending upwardly and backwardly and then bent upon itself to form 10 thread guides, a thread-controlling cam cooperating with said thread guides, and

means for operating said cam; substantially RUSSEL G. WOODWARD.

Witnesses:

CHESTER MONEIL, A. B. CLOTHIER. 

